title: A 3 T sodium and proton composite array breast coil.
abstract: OBJECTIVE
  The objective of this study was to determine whether a sodium phased array would improve sodium breast MRI at 3 T. The secondary objective was to create acceptable proton images with the sodium phased array in place.
  
  
  METHODS
  A novel composite array for combined proton/sodium 3 T breast MRI is compared with a coil with a single proton and sodium channel. The composite array consists of a 7-channel sodium receive array, a larger sodium transmit coil, and a 4-channel proton transceive array. The new composite array design utilizes smaller sodium receive loops than typically used in sodium imaging, uses novel decoupling methods between the receive loops and transmit loops, and uses a novel multichannel proton transceive coil. The proton transceive coil reduces coupling between proton and sodium elements by intersecting the constituent loops to reduce their mutual inductance. The coil used for comparison consists of a concentric sodium and proton loop with passive decoupling traps.
  
  
  RESULTS
  The composite array coil demonstrates a 2-5× improvement in signal-to-noise ratio for sodium imaging and similar signal-to-noise ratio for proton imaging when compared with a simple single-loop dual resonant design.
  
  
  CONCLUSIONS
  The improved signal-to-noise ratio of the composite array gives breast sodium images of unprecedented quality in reasonable scan times.
authors.affiliation: Department of Radiology, Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, USA; Department of Physics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Kaggie
authors.forename: J Rock
authors.initials: JR
authors.lastname: Hadley
authors.forename: James
authors.initials: J
authors.lastname: Badal
authors.forename: John R
authors.initials: JR
authors.lastname: Campbell
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Park
authors.forename: Dennis L
authors.initials: DL
authors.lastname: Parker
authors.forename: Glen
authors.initials: G
authors.lastname: Morrell
authors.forename: Rexford D
authors.initials: RD
authors.lastname: Newbould
authors.forename: Ali F
authors.initials: AF
authors.lastname: Wood
authors.forename: Neal K
authors.initials: NK
authors.lastname: Bangerter
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis*; D004867:Equipment Design; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D011522:Protons; D012964:Sodium
chemical_list: D011522:Protons; D012964:Sodium
keywords: RF coil; breast cancer; decoupling; metabolic imaging; phased array; sodium